Steering arrangement for boats



Dec. 27, 1966 c. NORTON 3,294,054

STEERING ARRANGEMENT FOR BOATS Filed Sept. 29, 1964 2 Sheets-Sheet 1 1966 c. NORTON 3294,54

STEERING ARRANGEMENT FOR BQATS Filed Sept. 29, 1964 2 Sheets-Sheet 2 Fawn K!) .156 115001557 mam Jimfim 02W, 72W M05221, 3 5% United States Patent Ofiice 3,294,654 Patented Dec. 27, 1966 3,294,954 STEERENG ARRANGEMENT FOR BOATS Calhoun Norton, 2617 Greenleaf 8t,

' Glenview, ill. 60%25 Filled Sept. 29, 1964, Ser. No. 464M351 9 Claims. (Cl. 11537) This invention relates to a steering mechanism for a boat, and more particularly relates to an improved steering mechanism for a boat powered by twin screws to provide superior maneuverability.

One of the problems encountered in the steering of a boat powered by turnable twin screws such as provided by outboard engines and inboard-outboard drives results from deviations of the axes of the screws from a desired relationship with respect to each other. For example it is frequently desirable that the shafts or axes of rotation of the two propellers be parallel while in other instances it may be desirable to position the propellers at angles with respect to each other in order to facilitate certain maneuvers.

It is an object of this invention to provide a novel and imroved steering mechanism for a boat powered by twin screws wherein the propellers and propeller shafts may be quickly and easily turned or adjusted relative to each other.

Another object of the invention is to provide a novel steering mechanism for a boat powered by twin screws for facilitating maneuvering of the boat for turning and docking by differential throttling and clutching.

Still another object of the invention is to provide a novel steering mechanism for a boat powered by twin screws whereby one propeller may be steered together with or separately from the other propeller and whereby the propellers may be turned simultaneously while maintaining a fixed angulation between the propeller shafts.

Another object of this invention is to provide a novel steering mechanism of the above described type which is of relatively simple, efficient and rugged construction.

Other objects and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side elevational view of an embodiment of the present invention in association with a houseboat powered by conventional twin screw inboard-outboard engines;

FIG. 2 is a plan view of the steering mechanism shown in FIG. 1;

FIG. 3 is a side elevational view, partially in section on an enlarged scale of the steering mechanism of FIGS. 1 and 2;

FIG. 3a is an enlarged fragmentary view showing a portion of the structure in greater detail;

FIG. 3b is a perspective view showing a modified form of the invention;

FIG. 4 is a front elevational view, partially in section, of the steering mechanism shown in FIG. 3;

FIG. 5 is a diagrammatic plan view showing the propellers and propeller shafts of the boat shown in FIGS. 1 and 2 in association with a vector diagram of the forces involved;

FIGS. 6-1 are vector diagrams illustrating the manner in which the boat is maneuvered utilizing the steering mechanism of the present invention.

Referring now more specifically to the drawings wherein like parts are designated by the same numerals throughout the various figures, a steering mechanism 20 in accordance with the invention is shown in FIGS. 1 and 2 as including a steering wheel assembly secured in position on the control panel 22 of a houseboat designated generally by the numeral 24 and conventionally powered by twin screw inboard-outboard drive system designated generally by the numerals 2d and 28. As will be understood other types of drive means could be used such as outboard engines mounted on the transom of the boat.

The inboard-outboard drive system 23 is positioned on the left or port side 30 of the houseboat and includes an engine 32 mounted within the boat providing the power for a port outboard drive unit 40 conventionally mounted on the boat transom 42 at the rear or stern of the boat.

The outboard drive unit 40* includes a propeller 44 mounted on the end of a propeller shaft 46 which extends in a generally horizontal position rearwardly with respect to the boat transom. A tiller or steering lever 48 is provided for swinging the drive unit to the left or right about a generally vertical pivot St to change the angle of thrust of the propeller with respect to a longitudinal axis 51 of the boat. Conventional throttle means are provided for controlling the engine 32. Conventional clutch and transmission means may also be provided for controlling and reversing the rotation of the propeller and hence control and reverse the direction of thrust or if desired the engine may be reversible.

A flexible steering line or cable 52 is provided on the port side of the boat and is connected at its rear end to the tiller or lever 48 for pivoting of the port drive unit to the left or right. Preferably, the flexible steering line or cable 52 comprises a flexible tubular conduit 53 and a push-pull element or wire 55 slidable within the conduit. One end of the wire is connected at 57 to the lever 48 and the other end is connected at 59 to the wheel assembly 21.

The inboard-outboard drive system 26 is mounted on a starboard side of the boat and includes an engine 58, providing the power for a starboard drive unit 60 including propeller 62, propeller shaft 64, and tiller or lever 65, all of which are identical to the corresponding components of the inboard-outboard drive system 28. A flexible steering lever or cable $8 is also provided on the starboard side of the boat and is connected at its rear end '70 to the steering lever for steering the propeller and propeller shaft of a starboard drive unit, that is for pivoting the starboard drive unit to the left or right in a horizontal plane about a generally vertical pivot '71. The push-pull element of the cable 68 has its opposite end connected at 73 to the steering wheel assembly as described more in detail below.

Conventional throttle, transmission and clutch control means are provided for the starboard drive system identical to but separate from the throttle, transmission and clutch control means for the port drive unit.

As shown best in FIGS. 3 and 4, the steering wheel assembly 21 includes individual control means for steering the port and starboard drive units and also means for maintaining the individual steering control means in a fixed predetermined relationship with respect to one another.

The steering assembly 21 includes first and second toothed racks, 74 and 76 which are mounted for reciprocable sliding movement in a generally horizontally extending position one behind the other. The first and second racks are connected respectively to forward ends of the flexible pushpull elements of the control cables 52 and 68 respectively at the points 59 and 73 mentioned above. The racks are operable by appropriate rack drive means to be hereafter described and upon reciprocable movement operate the flexible push-pull elements of the cables 52 and d8.

A steering wheel 84 is provided and secured to one end of a hollow shaft 86 journaled in a suitable bearing 87 mounted in the control panel 22. A toothed pinion 88 is fixed on an opposite end of the shaft in meshing engagement with the rack 76 for shifting the rack 76 laterally upon turning of the steering wheel 84.

The steering assembly 21 also includes a lever 90 fixedly mounted on one end of a rotatable shaft 92 running concentrically through the hollow shaft 86 and having a toothed pinion 94 at its other end. Pinion 94 is positioned on its shaft in meshing and driving engagement with the rack 74 for shifting the rack laterally for turning of the starboard drive unit.

Means is provided for releasably connecting the steering wheel 84 and the lever 90 and includes a plurality of arcuately spaced aperture 96 provided around the rim of the wheel 84 and a complementary spring-loaded pin 98 is mounted on the lever in position for selective insertion into the apertures 96.

Thus, the port or starboard drive units can be turned by the steering system of the present invention either separately or simultaneously either in parallel or at varying angles apart. More specifically, it is desired to steer the two drive units simultaneously with the propeller shafts parallel to one another, the spring-loaded pin 98 on the spoke 90 is inserted in a predetermined aperture in the wheel 84 so that the lever and wheel and thus the shafts 76 and 86 are locked for rotation in unison. Upon rotation of the steering wheel 84, both racks 74 and 76 are actuated and the drive units are turned simultaneously.

On the other hand, it may be desirable to steer the two drive units simultaneously but at a predetermined angle with respect to one another rather than with the propeller shafts parallel. This may also be done by withdrawing the spring-loaded pin 98 from the steering wheel aperture in which it is positioned and moving the lever 90 to the position desired at which time the spring-loaded pin may be again inserted in a predetermined aperture for again locking the lever to the wheel. Of course when the lever is adjusted relative to the wheel in this manner, the rack 74 will be adjusted relative to the rack 76 and the drive unit 40 will be turned and adjusted relative to the unit 60.

On other occasions, it may be desirable to turn the two drive units separately, and for this purpose, appropriate holding means is provided for the spring-loaded pin 98 to maintain the pin in a withdrawn position. For instance, a cotter pin, not shown, may be inserted transversely in a transverse slot provided in the pin 98 to hold the pin away from the wheel. Preferably, however, mating earns 101 and 103 are mounted on the pin and on the wheel so that when the pin 98 is manually rotated about its own axis in one direction it may be eammed outwardly or withdrawn from an aperture and when the pin is rotated in an opposite direction it is advanced by the spring for entry into an aperture. FIG. 3b shows a modified form of the invention which is essentially the same as the structure described abiove. This embodiment differs in that the apertures 96 and the pin 98 have been replaced by a clip 98b secured to the lever 90b and adapted to detachably interlock with the spokes 9612 on the wheel 84b.

For a fuller appreciation of the manner in which the invention operates, reference is now made to FIGS. 5-9 illustrating the manner in which exceptional boat maneuverability is achieved with the steering arrangement of the present invention.

FIG. 5 is a schematic plan view representation of the propeller shafts of a twin screw inboard-outboard boat. The steering arrangement of the present invention is utilized to turn the two propeller shafts 45 degrees inwardly with respect to the longitudinal axis of the boat with the lines of thrust of the two propellers intersecting at a point 105. To achieve this particular positioning of the propeller shafts, it is necessary to turn the steering wheel controlling the port propeller shaft all the Way to the left to turn the propeller shaft all the way to the right, that is, at a 45 degree angle to the longitudinal axis 107 of the boat. In addition, the spring-loaded pin on the lever 90 is disengaged from the steering wheel and the lever is turned all the way to the right to turn the starboard propeller shaft inwardly at a 45 degree angle as shown. While the shafts are shown turned inwardly at 45 degrees it is to be understood that the limit of inward movement of certain presently available drive units may be at different angles such for example as about 30 degrees. Furthermore, advantages of this system and method of operation can be had by adjusting the drive units to a wide variety of angles substantially deviating from a parallel relationship. Then the spring-loaded pin 98 is released int-o one of the apertures 96 provided in the steering wheel. It should be clear that in this position the steering wheel and the lever 90 are locked in position, that is, neither one of the two can be moved except by withdrawing the pin 98. In other words, since the two steering means for the port starboard propellers are locked together in opposite extremes of travel, the combination wheel cannot be steered.

It would be seem at first inspection of the manner in which the propellers are turned that such a situation would severely limit maneuverability of the boat. Actually, however, this position provides maximum maneuverability of the boat at low speeds and at low power for use around a congested harbor or for docking. Such superior maneuverability is accomplished by the technique of differential clutching and differential throttling as will be hereafter described. Any suitable throttle and reverse gear or clutch controls may be used. For example a control (FIG. 3) of known construction may be mounted at the control station 22 and is provided with levers 107 and 109 respectively adapted to operate both the throttles and reverse gears for the port and starboard engines. Of course separate throttle and reverse gear controls may be provided if desired.

Consider that it is desired to move forwardly with a boat in a congested harbor. Consider that in this situation, the starboard and port throttles are advanced to provide two units of thrust apiece, the port and starboard thrust being designated generally by the numerals 104 and 106 respectively.

A vector analysis of the forces involved, illustrated in FIG. 6, reveals that approximately three units of a resultant forward thrust are provided designated in FIG. 6 by the numeral 108. One advantage of this position is that the engines may be operated at relatively higher speeds for minimizing any possibility of rough operation or engine fracture without unduly increasing the resultant forward thrust and speed of the boat. Another advantage of this position is that too much power cannot be applied, in other words, with both clutches ahead and the propellers turning in the same direction and with the throttles advanced equally to attain the desired speed, too much power causes mutual interference of the slip streams of the two propellers and results in cavitation. Such a result is especially desirable in that it gives a clear and distinct warning to a heavy handed or excitable skipper that he is applying too much power and this situation may help to keep him steady and prevent him from bumping into the docks.

Now consider just the reverse situation, that is, with both clutches in reverse and with the propellers rotating in just the opposite direction from that illustrated in FIG. 6. Then both throttles are advanced equally to about two units of reverse thrust as designated generally by the numerals 110, 112 in FIGS. 5 and 7. In this situation the resultant thrust is approximately three units of reverse thrust as designated generally by the numeral 114. In this situation as in the forward position illustrated in FIG. 6, the application of excessive power results in a mutual interference of slip streams and cavitation, warning the skipper that he is applying too much power for use in a congested harbor or docking area.

Differential throttling or the use of differential power on the tWo propellers to turn the boat is very effective with exceptional maneuverability in either forward or reverse. Differential throttling is illustrated in FIG. 8. Consider that the propellers are turned inwardly as shown in FIG. 5, and that it is desired to make a forward throttle turn to the port side. In this case the port throttle is advanced to produce one unit of forward thrust designated by the numeral 118 and the starboard throttle is advanced to produce three units of forward thrust, the starboard thrust being designated by the numeral 120. As indicated by the vector diagram the resultant thrust designated by the numeral 122 is slightly over three units of thrust directed at an angle to the longitudinal axis of the boat and tending to move the stern of the boat to the starboard side for producing a port turn. By using no power whatsoever from the port engine, the resultant force approaches a direction of 45 degrees to the longitudinal axis of the boat. This differential throttling or steering by differential power is exceptionally effective and surprisingly sensitive in either direction forward or reverse, particularly when operating at relatively low speeds.

Maneuvering of the boat by the use of differential reversing is very spectacular, has very practical application and is illustrated in FIG. 9. In FIG. 9, the port propeller is reversed applying two units of thrust designated by the numeral 124; the starboard clutch is advanced applying about two units of thrust designated by the numeral 126. The resultant thrust designated by the numeral 128 is about three units of thrust, that is, greater thrust than that of either engine with a direction of about 90 degrees with respect to the longitudinal axis of the boat. In this condition the pivot point becomes the center of drag of the boat designated generally by the numeral 130 in FIGS. 2 and 5. Assuming the houseboat illustrated in FIG. 1 to be approximately 30 feet long and the center of drag to be located at approximately the center of the boat, that is, fifteen feet forwardly of the transom, and assuming that the propellers are about two feet behind the transom, and the point of intersection of the lines of force or thrust is at least several feet behind the propellers, the resultant force is effectively applied through a distance of over 20 feet with a moment of rotation of over 20 times three units or more than 60 units of moment of rotation.

To appreciate the significance of differential reversing, reference is made to FIG. illustrating a conventional turn to the port side of the boat wherein the propeller shafts are maintained in parallel and about two units of thrust to the rear are applied on the port propeller and about two units of forward thrust on the starboard propeller, the propeller thrust being designated generally by the numerals 131 and 132. In this situation, the moment of rotation is the result of the force times the lever or in this instance, assuming the distance between the two 'propeller shafts to be four feet, a total of four units of force acting through a distance of two feet to produce a moment of rotation of about eight units in comparison to the more than 60 units mentioned above.

FIG. 10 also illustrates the roblem of maintaining the two propeller shafts in parallel. With a conventional outboard or inboard-outboard twin screw arrangement, it is frequently found that the propellers are not exactly parallel for various reasons including possible slack in the steering system. In this instance, where it is desired to make a turn, it is found that the propeller shafts may diverge resulting in a much less efiicient turn than would normally be expected. With the steering system of the present invention it is a very simple matter relatively to adjust the two propeller shafts into a slightly angular relationship rather than into exact parallelism prior to beginning a turn so that the inherent tendency for the drive unit to pivot relative to each other as much as is allowed by the slack or flexibility in the steering system results in positioning of the drive shafts in substantially exact parallelism during the turn whereby a more efficient turn is achieved.

Referring again to FIG. 5, attention is directed to the dotted line position of the propellers which are turned outwardly so that the lines 135 and 137 of thrust intersect each other at a point within the boat. By proper adjustment, the lines 135 and 137 can be made to intersect at the center of drag 130. Then by operating one propeller forwardly and the other in reverse, a laterally direct resulting thrust 139 is provided at the point which will cause the boat to move substantially sideways.

While various examples of the manner of use of the present invention have been given, it should be clear that the invention is not to be limited thereto since other methods of using the invention will occur to those skilled in the art. Further-more various changes may be made in the structure shown and described herein without departing from the spirit and scope of the appended claims.

The invention is claimed as follows:

1. In a steering system for a boat powered by engine means including first and second spaced drive units respectively having first and second propellers respectively on first and second rotatable propeller shafts mounted for pivotal adjustment about upstanding axes and means for controlling the speed of rotation of said propellers, said steering system including first and second means for pivoting the first and second propeller shafts about said axes, first and second control means connected to the first and second means for independently pivoting the propeller shafts for selective positioning of said propeller shafts in predetermined relationship with respect to each other, and means connecting said first and second control means for enabling operator of said boat to steer said boat by simultaneously pivoting said first and second propeller shafts with the propeller shafts maintained at said predetermined relationship.

2. In a steering system for a boat powered by means including first and second drive units independently pivotable about upstanding axes and respectively having first and second propellers mounted respectively on first and second rotatable propeller shafts, said steering system including first and second means for pivoting the first and second propeller shafts about said axes, first and second control means respectively connected to the first and second means for independently pivoting the propeller shafts for selective positioning of said propeller shafts in predetermined relationship with respect to each other, means releasably connecting said first and second control means for enabling on operator of said boat to steer said boat by simultaneously pivoting said first and second propeller shafts with the propeller shafts maintained at said predetermined relationship.

3. In a steering system for a boat having first and second drive units independently pivotal about upstanding axes and respectively having first and second propeller shafts and first and second means connectable with said drive units and extending therefrom to a remote control station for pivoting said first and second propeller shafts about said axes, the combination comprising first and second control means mountable at said control station and respectively connectable to said first and second means for independently pivoting the propeller shafts for selective positioning of the shafts in predetermined relationship with respect to each other, and means at said control station extending between and releasably connecting said first and second control means.

4. A steering system, as defined in claim 3, wherein said first and second control means respectively comprise first and second shiftably mounted control members at said control station and adapted to be manually grasped and actuated, said connecting means extending between and releasably connecting first and second control members.

5. A steering system, as defined in claim 4, wherein said first and second control means comprise concentric telescoping and relatively rotatably first and second shafts mounted at said control station, said first and second control members respectively being fixedly mounted on said first and second shafts, and means respectively operatively 7 connecting said first and second shafts to said first and second means.

6. A steering system, as defined in claim 5, wherein said 7 last named means connecting said first and second shafts to said first and second means comprises first and second pinions respectively fixed on and rotatable with said first 7 and second shafts, and first and second reciprocable toothed rack members respectively meshing with first and second pinions and connectable to first and second means.

7. A steering system, as defined in claim 4 wherein said releasable connectable means comprises a pin element shiftably disposed on one of said control members, and aperture means in the other said control members alignable with and adapted to receive said pin element.

8. A steering system, as defined in claim 7, wherein said aperture means comprises a plurality of arcuately spaced apertures selectively alignable with said pin element for enabling said first and second control members selectively to be connected to each other in various rela tive angular relationships.

References Cited by the Examiner UNITED STATES PATENTS 3,143,995 8/1964 Koppen 1l537 3,208,300 9/1965 Morse 114144 X FOREIGN PATENTS 906,907 2/1954 Germany. 141,397 9/1960 Russia.

FERGUS S. MIDDLETON, Primary Examiner.

MILTON BUCHLER, Examiner,

20 T. MAJOR, Assistant Examiner. 

1. IN A STEERING SYSTEM FOR A BOAT POWERED BY ENGINE MEANS INCLUDING FIRST AND SECOND SPACED DRIVE UNITS RESPECTIVELYY HAVING FIRST AND SECOND PROPELLERS RESPECTIVELY ON FIRST AND SECOND ROTATABLE PROPELLER SHAFTS MOUNTED FOR PIVOTAL ADJUSTMENT ABOUT UPSTANDING AXES AND MEANS FOR CONTROLLING THE SPEED OF ROTATION SAID PROPELLERS, SAID STEERING SYSTEM INCLUDING FIRST AND SECOND MEANS FOR PIVOTING THE FIRST AND SECOND PROPELLER SHAFTS ABOUT SAID AXES, FIRST AND SECOND CONTROL MEANS CONNECTED TO THE FIRST AND SECOND MEANS FOR INDEPENDENTLY PIVOTING THE PROPELLER SHAFTS FOR SELECTIVE POSITIONING OF SAID PROPELLER SHAFTS IN PREDETERMINED RELATIONSHIP WITH RESPECT TO EACH OTHER, AND MEANS CONNECTING SAID FIRST AND SECOND CONTROL MEANS FOR ENABLING OPERATOR OF SAID BOAT TO STEER SAID BOAT BY SIMULTANEOUSLY PIVOTING SAID FIRST AND SECOND PROPELLER SHAFTS WITH THE PROPELLER SHAFTS MAINTAINED AT SAID PREDETERMINED RELATIONSHIP. 